Please be nice to help someone, Heyzap ads have been working for 5 minutes after they no longer appear! I added the publisher ID in buildbox after I exported the project in Xcode, The game was put in TestFLight, I installed it,5 minutes ads worked very well, exactly as they were set up. I got out of the game and and when I come back the ads disappeared, I tested it after 12 hours and it's the same. I mention that I only use advertisements from heyzap!(intersetial and Video). I using last version of buildbox.
I read here how to add heyzap ads: https://www.buildbox.com/forum/index.php?threads/simple-rewarded-video-implimentation.452/ @Andy said **you should not need to manually add the HeyZap framework**
Some ads are limited to how many times they will show on a specific device. If they stop showing it's because the inventory of ads ran out.